This program examines blocks that only partially intersect with community districts.

General information

The starting point for downloading most Census shapefiles is here. You can find more about the census redistricting files here.

It helps to know the FIPS (Federal Information Processing System) codes for Kansas (20) and Missouri (29).

The important counties for this program are

Cass County, MO (29037) Clay County, MO (29047) Jackson County, MO (29095) Johnson County, KS (20091) Leavenworth County, KS (20103) Platte County, MO (29165) Wyandotte County, KS (20209)

Load relevant files

library(sf)
## Linking to GEOS 3.9.0, GDAL 3.2.1, PROJ 7.2.1
library(tidyverse)
## -- Attaching packages --------------------------------------- tidyverse 1.3.1 --
## v ggplot2 3.3.5     v purrr   0.3.4
## v tibble  3.1.4     v dplyr   1.0.7
## v tidyr   1.1.3     v stringr 1.4.0
## v readr   2.0.1     v forcats 0.5.1
## -- Conflicts ------------------------------------------ tidyverse_conflicts() --
## x dplyr::filter() masks stats::filter()
## x dplyr::lag()    masks stats::lag()
library(magrittr)
## 
## Attaching package: 'magrittr'
## The following object is masked from 'package:purrr':
## 
##     set_names
## The following object is masked from 'package:tidyr':
## 
##     extract
path_name <- "../data/"
load(paste0(path_name, "bl", ".RData"))
glimpse(bl)
## Rows: 39,903
## Columns: 4
## $ bl_id    <chr> "200910518012010", "200910514003006", "200910515002005", "200~
## $ bl_name  <chr> "Block 2010", "Block 3006", "Block 2005", "Block 1009", "Bloc~
## $ bl_area  <dbl> 38500.823, 51711.677, 104537.047, 73933.762, 95854.528, 19934~
## $ geometry <POLYGON [°]> POLYGON ((-94.64213 38.9774..., POLYGON ((-94.63966 3~
load(paste0(path_name, "cd", ".RData"))
glimpse(cd)
## Rows: 59
## Columns: 4
## $ cd_id    <dbl> 106, 108, 113, 102, 129, 116, 114, 101, 105, 103, 107, 109, 1~
## $ cd_name  <chr> "East Side", "Old Northeast", "Greater Downtown", "Blue Valle~
## $ cd_area  <dbl> 281713850, 118237219, 181920811, 216842678, 412671242, 264282~
## $ geometry <POLYGON [°]> POLYGON ((-94.52337 39.0941..., POLYGON ((-94.50777 3~
load(paste0(path_name, "icd", ".RData"))
glimpse(icd)
## Rows: 15,748
## Columns: 19
## $ bl_id         <chr> "290950023002014", "290950063002017", "290950022003001",~
## $ bl_name       <chr> "Block 2014", "Block 2017", "Block 3001", "Block 3004", ~
## $ bl_area       <dbl> 14983.197, 9597.627, 18151.722, 18380.541, 17691.230, 17~
## $ st_id         <chr> "29", "29", "29", "29", "29", "29", "29", "29", "29", "2~
## $ co_id         <chr> "29095", "29095", "29095", "29095", "29095", "29095", "2~
## $ tr_id         <chr> "29095002300", "29095006300", "29095002200", "2909500220~
## $ bg_id         <chr> "290950023002", "290950063002", "290950022003", "2909500~
## $ people        <chr> "62", "0", "22", "26", "42", "49", "43", "0", "12", "20"~
## $ housing_units <chr> "18", "0", "9", "18", "22", "22", "14", "0", "1", "10", ~
## $ land_area     <chr> "14996", "9606", "18167", "18396", "17706", "17473", "32~
## $ water_area    <chr> "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "~
## $ block_lat     <chr> "+39.0894021", "+39.0439974", "+39.0932160", "+39.093298~
## $ block_lon     <chr> "-094.5318307", "-094.5610343", "-094.5240738", "-094.52~
## $ cd_id         <dbl> 106, 106, 106, 106, 106, 106, 106, 106, 106, 106, 106, 1~
## $ cd_name       <chr> "East Side", "East Side", "East Side", "East Side", "Eas~
## $ cd_area       <dbl> 281713850, 281713850, 281713850, 281713850, 281713850, 2~
## $ geometry      <GEOMETRY [°]> POLYGON ((-94.5324 39.0887,..., POLYGON ((-94.5~
## $ in_area       <dbl> 14983.19694, 9597.62653, 18151.72239, 18380.54058, 17691~
## $ pct_in        <dbl> 100.0000000, 100.0000000, 100.0000000, 100.0000000, 100.~

List blocks that are split between communities

icd                                    %>%
  mutate(dev=abs(pct_in-50))           %>%
  arrange(dev)                          -> dev
dev                                    %>%
  print(n=20)
## Simple feature collection with 15748 features and 19 fields
## Geometry type: GEOMETRY
## Dimension:     XY
## Bounding box:  xmin: -94.90847 ymin: 38.8247 xmax: -94.38535 ymax: 39.35635
## Geodetic CRS:  NAD83
## First 20 features:
##                   bl_id    bl_name    bl_area st_id co_id       tr_id
## 13731   202090440023008 Block 3008  38784.788    20 20209 20209044002
## 13731.1 202090440023008 Block 3008  38784.788    20 20209 20209044002
## 21619   290470208022021 Block 2021  53718.568    29 29047 29047020802
## 32452   290950130032035 Block 2035  14588.518    29 29095 29095013003
## 32452.1 290950130032035 Block 2035  14588.518    29 29095 29095013003
## 33457   290950163003006 Block 3006   8740.562    29 29095 29095016300
## 33457.1 290950163003006 Block 3006   8740.562    29 29095 29095016300
## 10843.2 202090402001004 Block 1004   1716.527    20 20209 20209040200
## 13509   202090430002016 Block 2016  12572.542    20 20209 20209043000
## 13509.1 202090430002016 Block 2016  12572.542    20 20209 20209043000
## 37499.1 291650302013030 Block 3030   2601.423    29 29165 29165030201
## 37499   291650302013030 Block 3030   2601.423    29 29165 29165030201
## 10843.1 202090402001004 Block 1004   1716.527    20 20209 20209040200
## 13517   202099805001033 Block 1033   8292.725    20 20209 20209980500
## 13517.1 202099805001033 Block 1033   8292.725    20 20209 20209980500
## 29503   290950124003004 Block 3004   2729.426    29 29095 29095012400
## 39142   291650302013032 Block 3032 306528.920    29 29165 29165030201
## 39142.1 291650302013032 Block 3032 306528.920    29 29165 29165030201
## 11734   202090430002019 Block 2019   4040.513    20 20209 20209043000
## 11734.1 202090430002019 Block 2019   4040.513    20 20209 20209043000
##                bg_id people housing_units land_area water_area   block_lat
## 13731   202090440023      0             0         0      38818 +39.0776326
## 13731.1 202090440023      0             0         0      38818 +39.0776326
## 21619   290470208022      0             1     53765          0 +39.2414677
## 32452   290950130032      0             0     14600          0 +38.9332667
## 32452.1 290950130032      0             0     14600          0 +38.9332667
## 33457   290950163003      0             0         0       8748 +39.0410114
## 33457.1 290950163003      0             0         0       8748 +39.0410114
## 10843.2 202090402001      0             0      1718          0 +39.1521906
## 13509   202090430002      0             0     12583          0 +39.0502035
## 13509.1 202090430002      0             0     12583          0 +39.0502035
## 37499.1 291650302013     24             1      2604          0 +39.2628936
## 37499   291650302013     24             1      2604          0 +39.2628936
## 10843.1 202090402001      0             0      1718          0 +39.1521906
## 13517   202099805001      0             0         0       8300 +39.0984894
## 13517.1 202099805001      0             0         0       8300 +39.0984894
## 29503   290950124003     20             2      2731          0 +39.0349930
## 39142   291650302013    141            65    306801          0 +39.2640389
## 39142.1 291650302013    141            65    306801          0 +39.2640389
## 11734   202090430002      0             0      4044          0 +39.0492891
## 11734.1 202090430002      0             0      4044          0 +39.0492891
##            block_lon cd_id               cd_name    cd_area     in_area
## 13731   -094.7434580   216     Muncie Industrial   71793697  19470.0171
## 13731.1 -094.7434580   214                Morris  197287075  19314.7708
## 21619   -094.4586843   122    Shoal Creek Valley  907142727  26475.4817
## 32452   -094.5274130   132         Hickman Mills  168097252   7178.7392
## 32452.1 -094.5274130   127        Bannister West  190962384   7409.7784
## 33457   -094.5209358   102           Blue Valley  216842678   4259.7065
## 33457.1 -094.5209358   101            Blue Ridge  381892901   4480.8555
## 10843.2 -094.6519222   203             Northeast  102304904    881.2921
## 13509   -094.6394875   210       Shawnee Heights   73299753   6478.9517
## 13509.1 -094.6394875   209              Rosedale   64911356   6093.5901
## 37499.1 -094.6009456   124                   KCI 1453755078   1347.3418
## 37499   -094.6009456   123              Gashland  511184945   1254.0810
## 10843.1 -094.6519222   219       Quindaro Bluffs   86913571    827.4271
## 13517   -094.6125643   208            Armourdale  113096389   4329.1369
## 13517.1 -094.6125643   202 Central Indust. Dist.   17353951   3963.5880
## 29503   -094.4371574   101            Blue Ridge  381892901   1301.9518
## 39142   -094.6251877   121     Line Creek Valley  588793273 146019.5571
## 39142.1 -094.6251877   124                   KCI 1453755078 160509.3970
## 11734   -094.6468606   211             Argentine  108911247   2117.4709
## 11734.1 -094.6468606   210       Shawnee Heights   73299753   1923.0426
##           pct_in       dev                       geometry
## 13731   50.20014 0.2001381 POLYGON ((-94.74175 39.0779...
## 13731.1 49.79986 0.2001381 POLYGON ((-94.74511 39.0772...
## 21619   49.28553 0.7144685 POLYGON ((-94.45635 39.2447...
## 32452   49.20815 0.7918528 POLYGON ((-94.5281 38.93329...
## 32452.1 50.79185 0.7918529 POLYGON ((-94.52675 38.9332...
## 33457   48.73493 1.2650735 POLYGON ((-94.52097 39.0430...
## 33457.1 51.26507 1.2650735 POLYGON ((-94.52094 39.0428...
## 10843.2 51.34157 1.3415739 POLYGON ((-94.65145 39.1529...
## 13509   51.53255 1.5325521 POLYGON ((-94.63498 39.0533...
## 13509.1 48.46745 1.5325521 POLYGON ((-94.64096 39.0492...
## 37499.1 51.79250 1.7924953 POLYGON ((-94.60092 39.2632...
## 37499   48.20750 1.7924953 POLYGON ((-94.60092 39.2625...
## 10843.1 48.20355 1.7964528 POLYGON ((-94.65153 39.1529...
## 13517   52.20403 2.2040337 POLYGON ((-94.61271 39.0988...
## 13517.1 47.79597 2.2040338 POLYGON ((-94.61239 39.0980...
## 29503   47.70056 2.2994359 POLYGON ((-94.43716 39.0353...
## 39142   47.63647 2.3635299 MULTIPOLYGON (((-94.62606 3...
## 39142.1 52.36354 2.3635412 MULTIPOLYGON (((-94.62261 3...
## 11734   52.40599 2.4059852 POLYGON ((-94.64736 39.0511...
## 11734.1 47.59401 2.4059854 POLYGON ((-94.64631 39.0477...

Map split blocks

for (i in 1:500) {
  cd                                   %>%
    filter(cd_id==dev$cd_id[i])         -> cd_i
  bl                                   %>%
    filter(bl_id==dev$bl_id[i])         -> bl_i
  ti <- paste0(
    cd_i$CD_NAME, ", ",
    bl_i$NAME20, ", ",
    round(dev$pct_in[i]), "%")
  cd_i                                 %>%
    ggplot(aes())                       +
      geom_sf(
        fill="white", 
        color="darkgreen")              +
      ggtitle(ti)                       +
      geom_sf(
        data=bl_i,
        aes(), 
        fill=NA,
        color="darkred")                -> map_i
  plot(map_i)
}